This invention relates to a process for making .beta.-aminoethyl sulfide derivatives of aliphatic mercaptans. This invention also relates to a process of making derivatives of .beta.-aminoethyl sulfides.
The literature shows that .beta.-aminoethyl sulfides have been prepared by reacting the corresponding mercaptan with ethylenimine (i.e., aziridine). See, for example, "Ethylenimine and Other Aziridines" by O. C. Dermer and G. E. Ham, Academic Press, N.Y. (1969), pages 230-234. The references cited in the Dermer et al. text indicate that the .beta.-aminoethyl sulfides have a variety of uses and that they are more difficult to prepare from aliphatic mercaptans than from aromatic mercaptans.
Lamb (U.S. Pat. No. 3,291,683) teaches that certain .beta.-aminoalkyl sulfides can be prepared by reacting an alkyl mercaptan with an unsaturated nitrile (e.g., acrylonitrile) followed by chemical or catalytic reduction of the nitrile group. Lamb states that the aminoethyl sulfides are useful in controlling fungi and bacteria.
Fikentscher et al. (U.S. Pat. No. 3,793,370) teaches that .beta.-aminoethyl sulfonium compounds are prepared by reacting a thioether with an aziridine and an acid. These compounds are, therefore, derivatives of the .beta.-aminoethyl sulfides prepared by our process. The .beta.-aminoethyl sulfonium compounds are curing agents, cross-linking agents, antistatic agents, emulsifiers, fungicides and valuable intermediates in the preparation of such agents.
The reaction of aromatic mercaptans with 2-oxazolines is well documented. There are only a few references which describe the reaction of aliphatic mercaptans with 2-oxazolines. None of the references utilize the class of catalysts described hereafter, so far as we are aware.